The present invention is related to a spin pack. More specifically, the present invention is related to a spin pack containing one or more electroformed plates.
Spin packs for manufacturing fiber from melt-process or solution-processed polymers are well known in the art. A monocomponent fiber spin pack receives a flowably processed stream of a polymer or a blend of polymers and distributes the polymer stream to the spin holes to form a multitude of filaments. A multicomponent conjugate fiber spin pack contains a more complicated distribution system that separately distributes the streams of the component polymers in predetermined positions into the spinning holes to form unitary filaments from each hole.
In general, a spin pack is designed to have a number of modular sections or plates such that the spin pack can be easily cleaned and each plate can be replaced with a new or different plate. Conventionally, the sections or plates of a spin pack are metal articles that are individually precision milled or cut from a metal block to have various channels and bores. Consequently, the production of a spin pack is highly laborious and costly, and it is highly laborious and difficult to produce exact duplicates of a spin pack or plates of a spin pack.
Producing a spin pack for multicomponent conjugate filaments exacerbates the cost and reproducibility problem since a conjugate filament spin pack requires a complicated distribution design that allows precise distribution of different streams of flowably processed polymer compositions throughout the spin pack without allowing intermixing of the streams.
There have been attempts to find less costly methods for producing spin pack plates. One example of such attempts uses a photo-chemical etching process to produce plates for a spin pack. Although the cost of producing etched plates is relatively lower than milled plates, a chemical etching process is not as accurate as a milling process, and thus, the etching production process does not eliminate the reproducibility problem.
There remains a need for a spin pack production process that is less costly and yet highly precise and reproducible.